Levels of Trihalomethanes in Stored Water from High and Fundamental Schools: Comparison between Two Temporal Data Sets

Abstract

Epidemiological studies have been investigating the relationship between chlorination byproducts exposure and cancer. Studies showed the incidence of colon, rectum and bladder cancer in laboratory animals when halogenated byproducts were administered to them, such as trihalomethanes. Based on this fact, in this work, two data sets of water quality parameters were analyzed with focus on total trihalomethanes (THMt). These two data sets are from two different time periods (one in 2014 and other in 2017). All the samples were collected in the same months, in both data sets. The samples were taken from its same corresponding sampling points in both periods of time. Trihalomethanes (THMs) are undesired byproducts of chlorination and its formation occurs when the chlorine used in water treatment reacts with natural organic matter, which is present in natural waters, during the disinfection process. The aim of this research was to investigate the THMs levels in storage water from the chlorination performed by the Water Treatment Station (WTS) of the Maringá-Parana-Brazil; also, to compare the results obtained with the maximum allowable values (MAVs) established by the Consolidation Resolution n.05/2017, current law of water quality in Brazil. Water samples were collected in eight high and fundamental schools of Maringá-Paraná-Brazil and analyzed through the gas chromatography method by the use of mass spectrometry detector with purge-and-trap concentrator (GC-MS) for THM. Furthermore, parameters such as pH and residual chlorine were analyzed following the methodology proposed by the Standard Methods for the Examination of Water and Wastewater. The study results to THMt show that the maximum value of 21.5 µg/L obtained is within the MAV of 100 µg/L. Chloroform was

Monitoring and Assessment of the Quality of Chlorinated Water in Schools

“…The formation of DBPs depends on the nature and concentration of NOM, levels of bromide ions (Br − ) and chlorine (mainly residual chlorine), pH, and temperature [18]. Total THMs are formed by the sum of four species: trichloromethane (CHCl 3 ), bromodichloromethane (CHCl 2 Br), chlorodibromomethane (CHBr 2 Cl), and bromoform (CHBr 3 ) [16,19]. According to Annex XX of Consolidation Ordinance No.…”

“…Thus, it is necessary to monitor and carefully assess the physicochemical and microbiological aspects of treated water, particularly that supplied to schools, which mainly host children and adolescents [19]. In the present study, the monitoring and assessment of different water samples from schools were conducted to determine levels of THMs and potentially toxic metals as well as the relationship to the chlorination process.…”

Analysis of Haloacetic Acids (HAA5) in Waters of Public Schools and Residencies in Maringá-Brazil

“…The term HAA5 indicates the sum of five haloacetic acids: monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, bromoacetic acid and dibromoacetic acid [6]. These molecules are formed when natural organic compounds react with chlorine in two points of WTP in Maringá city: at the pre-chlorination and post-chlorination [2].…”

Data on THMs concentration and spatial trend in water distribution network (a preliminary study in center of Iran)

“… *Value of the Protocol: Trihalomethanes (THMs) produced in treated water due to the reaction between of chlorine and some natural organic matters. These byproducts compounds could lead to bladder, kidney, and liver cancers [1,2]. The obtained data about THMS with Arc GIS could be used for better understand the quality water distribution network in association with disinfection byproduct values in the study area.…”